You can receive a ticket for driving under the influence of alcohol on private property. However, you should not receive a suspension of your license under the Statutory Summary Suspension.
In Illinois a person can receive a charge of driving under the influence (DUI) anywhere within the State of Illinois, even in your driveway. For example, if your sitting in your car with the keys either in the ignition (so you can listen to the radio) and you had too much to drink, you can get a DUI. In Illinois you need to have “actual physical control” of the vehicle to be charged with DUI. “Actual physical control” has been interpreted by the courts to mean simply having the keys so you have ability to start and use the car.
Although you can obtain a DUI anywhere within the State of Illinois, you should not receive a Statutory Summary Suspension which is specifically limited to DUI which occur public property, road or public maintained roads.
I had a client that fell asleep while in the drive-thru at McDonalds. The police woke him up and arrested him for DUI. Although he received a Statutory Summary Suspension, I was able to have it rescinded because he was not on a public road.